Shrubs or perennial erect herbs with cystoliths. Leaves petiolate; leaf blade margin entire or crenate. Inflorescences terminal or rarely axillary, spikes, lax, sometimes several forming a panicle; bracts sometimes colored, subleaflike, large; bracteoles small, narrow. Calyx 5-lobed; lobes narrow, subequal. Corolla subsalverform; tube basally cylindric, long, slender, throat sometimes inconspicuous; limb 5-lobed; lobes obovate, subequal, contorted in bud. Stamens 2, inserted below throat; anthers 2-thecous; thecae parallel, muticous; staminodes 2, clavate or filiform. Ovary with 2 ovules per locule; style filiform, glabrous or pubescent; stigma 2-lobed, lobes unequal. Capsule with a solid stalk at base, clavate, 4-seeded; retinacula present. Seeds discoid, compressed, pubescent with hygroscopic trichomes.